The present invention relates to a machine press having a plurality of slides. More specifically, this invention relates to the coordination of pressing operations for each slide in a machine press having a plurality of slides.
In multi-slide machine presses that automatically perform multiple processing steps, the crank angle to be used in pressing must be within a fixed range based on the part to be processed. When a conveying device is used for the part to be processed, the pressing operation and the conveying operation of the part to be processed must be completed within a single cycle of operation at the machine press to maximize the efficiency of the press. When pressing is performed with a larger number of slides simultaneously, the processing load on the machine press increases.
In general, the nominal pressure of the machine press is based on a symmetrical distribution within a certain radius from the center of the machine press. Thus, when there is an eccentric load or an extremely concentrated load, there may be greater deformation of the machine press, an increase in vibrations, or more noise. The load from a pressing operation being performed by one slide may affect the others, possibly resulting in decreased precision. The slides being used for pressing operations requiring a high degrees of precision may be operated at decreased precision because of the eccentric loads or extremely concentrated loads.
One method of solving the problems associated with eccentric loads and extremely concentrated loads is to increase the size and strength of the various parts of the machine press, including the drive mechanism and the drive source, to handle the increased processing load required to drive the plurality of slides. This increases the cost of the press which limits the efficiency of a multi-slide press.